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Acta Crystallographica Section E: Structure Reports Online logoLink to Acta Crystallographica Section E: Structure Reports Online
. 2010 Mar 6;66(Pt 4):o754. doi: 10.1107/S1600536810007713

1,3-Dibenzyl-6-bromo-1H-imidazo[4,5-b]pyridin-2(3H)-one

S Dahmani a, Y Kandri Rodi a, F Capet b, El Mokhtar Essassi c, Seik Weng Ng d,*
PMCID: PMC2983860  PMID: 21580599

Abstract

The imidazopyridine fused-ring in the title compound, C20H16BrN3O, is planar (r.m.s. deviation = 0.011 Å). The phenyl rings of the benzyl substitutents twist away from the central five-membered ring in opposite directions; the rings are aligned at 61.3 (1) and 71.2 (1)° with respect to this ring.

Related literature

For the medicinal applications of 1,3-dihydro-imidazo[4,5-b]pyridin-2-ones, see: Barraclough et al. (1990 ▶); Cundy et al. (1997 ▶); Desarro et al. (1994 ▶); Liu et al. (2008 ▶); Mader et al. (2008 ▶); Zaki & Proença (2007 ▶). For the product of the reaction of propargyl bromide with 6-bromo-1,3-dihydro-imidazo[4,5-b]pyridin-2-one in DMF at room and high temperatures, see: Dahmani et al. (2010a ▶,b ▶).graphic file with name e-66-0o754-scheme1.jpg

Experimental

Crystal data

  • C20H16BrN3O

  • M r = 394.27

  • Monoclinic, Inline graphic

  • a = 9.1627 (1) Å

  • b = 25.5071 (3) Å

  • c = 8.0629 (1) Å

  • β = 115.571 (1)°

  • V = 1699.84 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.43 mm−1

  • T = 293 K

  • 0.42 × 0.18 × 0.13 mm

Data collection

  • Bruker X8 APEX2 diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T min = 0.428, T max = 0.743

  • 38010 measured reflections

  • 3903 independent reflections

  • 2967 reflections with I > 2σ(I)

  • R int = 0.036

Refinement

  • R[F 2 > 2σ(F 2)] = 0.041

  • wR(F 2) = 0.138

  • S = 1.07

  • 3903 reflections

  • 226 parameters

  • H-atom parameters constrained

  • Δρmax = 0.84 e Å−3

  • Δρmin = −0.90 e Å−3

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810007713/hg2651sup1.cif

e-66-0o754-sup1.cif (18.7KB, cif)

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810007713/hg2651Isup2.hkl

e-66-0o754-Isup2.hkl (191.3KB, hkl)

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

We thank Université Sidi Mohammed Ben Abdallah, Université Mohammed V-Agdal and the University of Malaya for supporting this study.

supplementary crystallographic information

Comment

Imidazo[4,5-b]pyridines are precursors for the synthesis of a variety of medicinal agents as compounds having the imidazo[4,5-b]pyridine fused-ring system possess a broad range of pharmacological activities (Barraclough et al., 1990; Cundy et al., 1997; Desarro et al., 1994; Liu et al., 2008; Mader et al., 2008; Zaki & Proença, 2007).

The present study represents the synthesis of the substituted an imidazo[4,5-b]pyridin-2-one derivative by the direct action of benzyl chloride on 6-bromo-1,3-dihydro-imidazo[4,5-b]pyridin-2-one in boiling DMF.

The imidazopyridine fused-ring in C20H16BrN3O (Scheme I, Fig. 1) is planar (r.m.s. deviation 0.011 Å). The phenyl rings of the benzyl substitutents twist away from the central five-membered ring in opposite directions; the rings are aligned at 61.3 (1) and 71.2 (1) ° with respect to this ring.

The temperature of the reaction, in the case of propargyl bromide, governs the nature of the product (Dahmani et al., 2010a, 2010b).

Experimental

To a mixture of 6-bromo-1,3-dihydro-imidazo[4,5-b]pyridin-2-one (1 mmol), potassium carbonate (4 mmol) and benzyltributylammonium chloride (0.1 mmol) in DMF was added benzyl chloride (2.5 mmol). The mixture was stirred for 48 hours. After completion of reaction (monitored by TLC), the inorganic salt was filtered and the solvent was removed under reduced pressure. The residue was purified by column chromatography on silica gel with ethyl acetate/hexane (1/1) as eluent. Colorless crystals were isolated when the solvent was allowed to evaporate.

Refinement

Carbon-bound H-atoms were placed in calculated positions (C—H 0.93-0.97 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2U(C).

Figures

Fig. 1.

Fig. 1.

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Thermal ellipsoid plot (Barbour, 2001) of C20H16BrN3O at the 50% probability level; hydrogen atoms are drawn as arbitrary radius.

Crystal data

C20H16BrN3O F(000) = 800
Mr = 394.27 Dx = 1.541 Mg m−3
Monoclinic, P21/c Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc Cell parameters from 9890 reflections
a = 9.1627 (1) Å θ = 2.5–25.0°
b = 25.5071 (3) Å µ = 2.43 mm−1
c = 8.0629 (1) Å T = 293 K
β = 115.571 (1)° Prism, colorless
V = 1699.84 (3) Å3 0.42 × 0.18 × 0.13 mm
Z = 4
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Data collection

Bruker X8 APEX2 diffractometer 3903 independent reflections
Radiation source: fine-focus sealed tube 2967 reflections with I > 2σ(I)
graphite Rint = 0.036
φ and ω scans θmax = 27.5°, θmin = 1.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) h = −11→11
Tmin = 0.428, Tmax = 0.743 k = −33→33
38010 measured reflections l = −9→10
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Refinement

Refinement on F2 Primary atom site location: structure-invariant direct methods
Least-squares matrix: full Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041 Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.138 H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0688P)2 + 1.1691P] where P = (Fo2 + 2Fc2)/3
3903 reflections (Δ/σ)max = 0.001
226 parameters Δρmax = 0.84 e Å−3
0 restraints Δρmin = −0.90 e Å−3
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Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

x y z Uiso*/Ueq
Br1 0.75465 (4) 0.225888 (14) 0.48173 (6) 0.07328 (18)
O1 0.2072 (3) 0.45942 (8) 0.3332 (3) 0.0570 (5)
N1 0.3210 (3) 0.28134 (9) 0.4493 (3) 0.0480 (6)
N2 0.2208 (3) 0.36984 (9) 0.3920 (3) 0.0399 (5)
N3 0.4318 (3) 0.40833 (8) 0.3767 (3) 0.0398 (5)
C1 0.4498 (4) 0.25184 (12) 0.4685 (4) 0.0515 (7)
H1 0.4465 0.2160 0.4879 0.062*
C2 0.5858 (4) 0.27231 (11) 0.4606 (4) 0.0473 (7)
C3 0.6008 (3) 0.32553 (11) 0.4321 (4) 0.0428 (6)
H3 0.6926 0.3396 0.4275 0.051*
C4 0.4695 (3) 0.35553 (10) 0.4115 (3) 0.0366 (5)
C5 0.3351 (3) 0.33129 (10) 0.4207 (3) 0.0366 (5)
C6 0.2777 (3) 0.41774 (10) 0.3635 (4) 0.0401 (6)
C7 0.0593 (3) 0.36191 (13) 0.3822 (4) 0.0482 (7)
H7A 0.0226 0.3269 0.3356 0.058*
H7B −0.0145 0.3867 0.2952 0.058*
C8 0.0513 (3) 0.36830 (10) 0.5637 (4) 0.0376 (5)
C9 0.0052 (3) 0.41597 (11) 0.6102 (4) 0.0448 (6)
H9 −0.0162 0.4444 0.5310 0.054*
C10 −0.0090 (4) 0.42129 (13) 0.7723 (4) 0.0530 (7)
H10 −0.0399 0.4533 0.8023 0.064*
C11 0.0223 (4) 0.37940 (15) 0.8905 (4) 0.0572 (8)
H11 0.0105 0.3829 0.9989 0.069*
C12 0.0711 (4) 0.33231 (14) 0.8480 (5) 0.0581 (8)
H12 0.0946 0.3042 0.9291 0.070*
C13 0.0854 (3) 0.32658 (12) 0.6849 (4) 0.0490 (7)
H13 0.1180 0.2946 0.6565 0.059*
C14 0.5321 (4) 0.44829 (11) 0.3487 (4) 0.0431 (6)
H14A 0.6349 0.4498 0.4570 0.052*
H14B 0.4797 0.4821 0.3362 0.052*
C15 0.5641 (3) 0.43916 (9) 0.1821 (3) 0.0349 (5)
C16 0.6900 (3) 0.46603 (11) 0.1695 (4) 0.0437 (6)
H16 0.7526 0.4889 0.2630 0.052*
C17 0.7240 (4) 0.45935 (14) 0.0203 (4) 0.0549 (8)
H17 0.8092 0.4777 0.0137 0.066*
C18 0.6319 (4) 0.42548 (13) −0.1197 (4) 0.0533 (7)
H18 0.6559 0.4204 −0.2194 0.064*
C19 0.5046 (4) 0.39937 (12) −0.1105 (4) 0.0498 (7)
H19 0.4411 0.3770 −0.2055 0.060*
C20 0.4702 (3) 0.40613 (11) 0.0401 (4) 0.0445 (6)
H20 0.3836 0.3884 0.0453 0.053*
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Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23
Br1 0.0600 (2) 0.0554 (2) 0.0961 (3) 0.01808 (15) 0.0259 (2) 0.00089 (17)
O1 0.0630 (13) 0.0486 (12) 0.0681 (14) 0.0147 (10) 0.0364 (11) 0.0062 (10)
N1 0.0528 (14) 0.0437 (13) 0.0526 (14) −0.0072 (10) 0.0274 (12) 0.0003 (10)
N2 0.0410 (11) 0.0455 (12) 0.0394 (12) −0.0017 (9) 0.0233 (10) −0.0020 (9)
N3 0.0454 (12) 0.0371 (11) 0.0455 (12) −0.0015 (9) 0.0277 (10) 0.0009 (9)
C1 0.0595 (18) 0.0372 (15) 0.0584 (18) −0.0029 (13) 0.0261 (15) 0.0018 (13)
C2 0.0459 (15) 0.0424 (15) 0.0494 (16) 0.0071 (12) 0.0166 (13) −0.0007 (12)
C3 0.0398 (13) 0.0436 (14) 0.0478 (15) 0.0001 (11) 0.0214 (12) −0.0026 (12)
C4 0.0424 (13) 0.0371 (12) 0.0336 (12) −0.0029 (10) 0.0194 (11) −0.0028 (10)
C5 0.0392 (13) 0.0400 (13) 0.0336 (12) −0.0026 (10) 0.0186 (10) −0.0031 (10)
C6 0.0482 (15) 0.0438 (14) 0.0346 (13) 0.0014 (12) 0.0239 (11) −0.0020 (11)
C7 0.0359 (13) 0.0663 (19) 0.0426 (15) −0.0056 (12) 0.0172 (12) −0.0081 (13)
C8 0.0291 (11) 0.0463 (14) 0.0404 (13) −0.0053 (10) 0.0177 (10) −0.0025 (11)
C9 0.0402 (14) 0.0445 (15) 0.0506 (16) 0.0020 (11) 0.0204 (12) 0.0050 (12)
C10 0.0482 (16) 0.0594 (18) 0.0570 (18) 0.0009 (14) 0.0279 (14) −0.0135 (15)
C11 0.0468 (16) 0.090 (2) 0.0415 (16) −0.0001 (16) 0.0251 (13) −0.0038 (16)
C12 0.0531 (18) 0.069 (2) 0.0566 (19) 0.0009 (15) 0.0276 (15) 0.0177 (16)
C13 0.0460 (15) 0.0441 (15) 0.0637 (18) 0.0007 (12) 0.0302 (14) 0.0014 (13)
C14 0.0544 (16) 0.0379 (13) 0.0447 (15) −0.0103 (12) 0.0287 (13) −0.0057 (11)
C15 0.0382 (12) 0.0309 (12) 0.0383 (13) 0.0023 (10) 0.0190 (11) 0.0031 (10)
C16 0.0412 (14) 0.0442 (15) 0.0437 (15) −0.0059 (11) 0.0166 (12) 0.0001 (11)
C17 0.0486 (17) 0.066 (2) 0.0605 (19) −0.0051 (14) 0.0338 (16) 0.0068 (15)
C18 0.0600 (18) 0.0642 (19) 0.0467 (16) 0.0081 (15) 0.0333 (15) 0.0053 (14)
C19 0.0571 (17) 0.0519 (16) 0.0401 (15) −0.0015 (13) 0.0206 (13) −0.0074 (12)
C20 0.0460 (15) 0.0461 (15) 0.0463 (15) −0.0085 (12) 0.0245 (13) −0.0048 (12)
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Geometric parameters (Å, °)

Br1—C2 1.897 (3) C9—H9 0.9300
O1—C6 1.213 (3) C10—C11 1.377 (5)
N1—C5 1.311 (3) C10—H10 0.9300
N1—C1 1.351 (4) C11—C12 1.376 (5)
N2—C5 1.382 (3) C11—H11 0.9300
N2—C6 1.386 (3) C12—C13 1.384 (5)
N2—C7 1.462 (3) C12—H12 0.9300
N3—C4 1.389 (3) C13—H13 0.9300
N3—C6 1.391 (3) C14—C15 1.512 (4)
N3—C14 1.453 (3) C14—H14A 0.9700
C1—C2 1.377 (4) C14—H14B 0.9700
C1—H1 0.9300 C15—C20 1.382 (4)
C2—C3 1.393 (4) C15—C16 1.383 (4)
C3—C4 1.374 (4) C16—C17 1.377 (4)
C3—H3 0.9300 C16—H16 0.9300
C4—C5 1.408 (4) C17—C18 1.382 (5)
C7—C8 1.505 (4) C17—H17 0.9300
C7—H7A 0.9700 C18—C19 1.372 (5)
C7—H7B 0.9700 C18—H18 0.9300
C8—C13 1.386 (4) C19—C20 1.391 (4)
C8—C9 1.390 (4) C19—H19 0.9300
C9—C10 1.376 (4) C20—H20 0.9300
C5—N1—C1 114.4 (2) C9—C10—C11 120.3 (3)
C5—N2—C6 110.0 (2) C9—C10—H10 119.9
C5—N2—C7 126.0 (2) C11—C10—H10 119.9
C6—N2—C7 123.9 (2) C12—C11—C10 119.9 (3)
C4—N3—C6 109.8 (2) C12—C11—H11 120.1
C4—N3—C14 126.4 (2) C10—C11—H11 120.1
C6—N3—C14 123.8 (2) C11—C12—C13 120.2 (3)
N1—C1—C2 123.1 (3) C11—C12—H12 119.9
N1—C1—H1 118.4 C13—C12—H12 119.9
C2—C1—H1 118.4 C12—C13—C8 120.2 (3)
C1—C2—C3 122.2 (3) C12—C13—H13 119.9
C1—C2—Br1 118.6 (2) C8—C13—H13 119.9
C3—C2—Br1 119.2 (2) N3—C14—C15 114.1 (2)
C4—C3—C2 114.8 (3) N3—C14—H14A 108.7
C4—C3—H3 122.6 C15—C14—H14A 108.7
C2—C3—H3 122.6 N3—C14—H14B 108.7
C3—C4—N3 133.9 (2) C15—C14—H14B 108.7
C3—C4—C5 119.3 (2) H14A—C14—H14B 107.6
N3—C4—C5 106.9 (2) C20—C15—C16 118.8 (2)
N1—C5—N2 126.6 (2) C20—C15—C14 122.7 (2)
N1—C5—C4 126.2 (3) C16—C15—C14 118.5 (2)
N2—C5—C4 107.2 (2) C17—C16—C15 120.9 (3)
O1—C6—N2 126.9 (3) C17—C16—H16 119.6
O1—C6—N3 127.0 (3) C15—C16—H16 119.6
N2—C6—N3 106.1 (2) C16—C17—C18 120.1 (3)
N2—C7—C8 113.9 (2) C16—C17—H17 120.0
N2—C7—H7A 108.8 C18—C17—H17 120.0
C8—C7—H7A 108.8 C19—C18—C17 119.6 (3)
N2—C7—H7B 108.8 C19—C18—H18 120.2
C8—C7—H7B 108.8 C17—C18—H18 120.2
H7A—C7—H7B 107.7 C18—C19—C20 120.3 (3)
C13—C8—C9 118.9 (2) C18—C19—H19 119.8
C13—C8—C7 120.7 (3) C20—C19—H19 119.8
C9—C8—C7 120.3 (3) C15—C20—C19 120.3 (3)
C10—C9—C8 120.4 (3) C15—C20—H20 119.9
C10—C9—H9 119.8 C19—C20—H20 119.9
C8—C9—H9 119.8
C5—N1—C1—C2 0.6 (4) C4—N3—C6—N2 0.4 (3)
N1—C1—C2—C3 0.0 (5) C14—N3—C6—N2 177.7 (2)
N1—C1—C2—Br1 −178.0 (2) C5—N2—C7—C8 92.2 (3)
C1—C2—C3—C4 −0.4 (4) C6—N2—C7—C8 −91.5 (3)
Br1—C2—C3—C4 177.6 (2) N2—C7—C8—C13 −86.0 (3)
C2—C3—C4—N3 −178.0 (3) N2—C7—C8—C9 95.7 (3)
C2—C3—C4—C5 0.1 (4) C13—C8—C9—C10 −1.1 (4)
C6—N3—C4—C3 178.2 (3) C7—C8—C9—C10 177.2 (3)
C14—N3—C4—C3 0.9 (5) C8—C9—C10—C11 0.0 (4)
C6—N3—C4—C5 −0.1 (3) C9—C10—C11—C12 1.3 (5)
C14—N3—C4—C5 −177.4 (2) C10—C11—C12—C13 −1.4 (5)
C1—N1—C5—N2 178.3 (3) C11—C12—C13—C8 0.3 (5)
C1—N1—C5—C4 −1.0 (4) C9—C8—C13—C12 1.0 (4)
C6—N2—C5—N1 −178.9 (3) C7—C8—C13—C12 −177.3 (3)
C7—N2—C5—N1 −2.1 (4) C4—N3—C14—C15 62.6 (4)
C6—N2—C5—C4 0.5 (3) C6—N3—C14—C15 −114.3 (3)
C7—N2—C5—C4 177.3 (2) N3—C14—C15—C20 18.6 (4)
C3—C4—C5—N1 0.6 (4) N3—C14—C15—C16 −163.1 (2)
N3—C4—C5—N1 179.2 (3) C20—C15—C16—C17 −1.3 (4)
C3—C4—C5—N2 −178.8 (2) C14—C15—C16—C17 −179.7 (3)
N3—C4—C5—N2 −0.2 (3) C15—C16—C17—C18 0.1 (5)
C5—N2—C6—O1 179.4 (3) C16—C17—C18—C19 1.2 (5)
C7—N2—C6—O1 2.6 (4) C17—C18—C19—C20 −1.2 (5)
C5—N2—C6—N3 −0.5 (3) C16—C15—C20—C19 1.4 (4)
C7—N2—C6—N3 −177.4 (2) C14—C15—C20—C19 179.7 (3)
C4—N3—C6—O1 −179.6 (3) C18—C19—C20—C15 −0.1 (5)
C14—N3—C6—O1 −2.2 (4)
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Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HG2651).

References

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  3. Bruker (2008). APEX2 and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.
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  5. Dahmani, S., Haoudi, A., Capet, F., Essassi, E. M. & Ng, S. W. (2010a). Acta Cryst. E66, o755. [DOI] [PMC free article] [PubMed]
  6. Dahmani, S., Haoudi, A., Capet, F., Essassi, E. M. & Ng, S. W. (2010b). Acta Cryst. E66, o756. [DOI] [PMC free article] [PubMed]
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  9. Mader, M., de Dios, A., Shih, C., Bonjouklian, R., Li, T. C., White, W., de Uralde, B. L., Sánchez-Martinez, C., del Prado, M., Jaramillo, C., de Diego, E., Cabrejas, L. M. M., Dominguez, C., Montero, C., Shepherd, T., Dally, R., Toth, J. E., Chatterjee, A., Pleite, S., Blanco-Urgoiti, J., Perez, L., Barberis, M., Lorite, M. J., Jambrina, E., Nevill, C. R., Lee, P. A., Schultz, R. C., Wolos, J. A., Li, L. C., Campbell, R. M. & Anderson, B. D. (2008). Bioorg. Med. Chem. Lett.18, 179–183. [DOI] [PubMed]
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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810007713/hg2651sup1.cif

e-66-0o754-sup1.cif (18.7KB, cif)

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810007713/hg2651Isup2.hkl

e-66-0o754-Isup2.hkl (191.3KB, hkl)

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography

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